This invention relates to an apparatus and method for improving the awareness of vehicle drivers or other persons such as ship captains and airplane pilots.
Recently, as a result of road network improvements the moving ability of vehicles has been considerably improved and more people spend a considerable amount of time driving. In general, drivers tend to drive their vehicle regardless of whether they are tired. If the driver operates the vehicle for an extended time without rest, fatigue sets in, which leads to decreased awareness of the driver and therefore the possibility of an accident.
To prevent this, an apparatus has been proposed wherein a signal for requesting a driver's response is provided at a time interval, and a decrease in driver awareness is determined from a response time of the driver to the given signal. However, in such an apparatus, a response may be required while the driver is traveling on a city road or curved road where the driver must concentrate on driving, and therefore, the driver's response may be long even though the driver's awareness level is high.
Other conventional apparatus monitor the driver's physical condition and, when a normal operation limit is exceeded, the driver is notified. Such an apparatus is disclosed in Japanese Patent Publication Laid-open (Japanese OPI) 59-22537. A heartbeat rate is increased or decreased according to driving force, mental stress, or a sensation of fear. Therefore, in the apparatus disclosed in Japanese OPI 59-22537, the driver's heartbeat rate is measured by a heartbeat sensor, and a determination is made as to whether or not a period of pulsation is within a preset tolerable range to determine the level of awareness of the driver.
Japanese Patent Publication Laid-open (Japanese OPI) 56-2227 generates a preliminary warning when a monotonous driving condition is detected, and a true warning is generated when the driver's reaction time exceeds a predetermined time, thereby determining the driver's level of awareness in two steps.
In Japanese OPI 59-22537, the heartbeat rate of the driver during driving is compared with a preset reference value to determine the level of awareness of the driver, and the reference value is fixed. However, the heartbeat rate depends on the individual driver and is affected by road in operating conditions. When the reference value of the heartbeat rate for determining the level of awareness is fixed, and a warning is generated according to the determination result, a warning may be given when the level of awareness of the driver is high or the warning may not be given when the level of awareness is low.
Japanese OPI 56-2227 determines the level of awareness of the driver in two steps, wherein the level of awareness is determined independently, and the fact that a decrease in the driver's level of awareness may occur over time is not considered.
Therefore, there is a danger that when driving is continued after an indication of decreased awareness, for example, the output of a preliminary warning, the level of awareness cannot be determined, and an appropriate warning cannot be output according to the actual level of awareness of the driver.
A primary object of the present invention is to provide an apparatus and method for improving the awareness of vehicle drivers which solve the above-identified problems.